Do you use let's encrypt?

Analysing performance problems with systemd

Now that Systemd is the default init-system in fresh installations of Debian GNU/Linux it is worth highlighting some of the new features.

One thing that Systemd is designed to do is speed up the booting of systems. True most installations are "servers" and as-such they're rarely rebooted, but I've been living with and working with a Debian laptop and Debian desktop for the past few years - and the laptop gets shutdown every day, and for that reason it is interesting to see how long a boot takes, and where that time is taken.

Three interesting commands to look at the boot-speed of a system are:

systemd-analyze

systemd-analyze critical-chain

systemd-analyze blame

This allow you to see the times that are taken to start various things. For example the second command on this laptop shows me:

Where are these systemd commands such as 'systemd-analyze' documented? Are there other systemd commands like this that one can explore? None of this seems to be clearly documented, I only hear about these switches such as '-analyze' from places such as the Arch Wiki or a post like this one. Where is the official sytemd documentation? I would love to have a copy of my own. Something nice and in-depth and comprehensive.

What others functions are there to explore besides the '-analyze' function?

Pretty much every binary installed with systemd has a man-page, which means that you should have the documentation locally. However I agree that things could be improved with a decent top-level overview.

I found the "The systemd for Administrators Blog Series" enormously helpful in giving a good flavour of options and capabilities; you can find that here on the official website:

systemd is not only init system with convenient terminology to express dependencies in a sane fashion.
For me main input is: good mechanisms to isolate services into descrete "slices" (using cgroups, i.e. containers),
I believe yet another level of isolation is a good thing.
Another good thing is journald, which so happens to be is a nice systemd side effect (the moment you learn how to use it)
systemd-analyze can also show you boot log BEFORE "traditional" logging daemons started, which is also handy.